I. FIELD OF THE INVENTION
This invention pertains to collating or insertion machines, and particularly to such machines wherein a group of related items are stuffed or inserted into a packaging medium such as an envelope
II. PRIOR ART AND OTHER CONSIDERATIONS
In a conventional insertion machine, series of related items, such as documents commonly referred to as "inserts", are associated together and inserted or "stuffed" into an awaiting, flap-opened envelope. Thereafter the stuffed envelope is sealed and various other operations can be performed, such as associating the stuffed envelopes with an appropriate postage weight category and/or grouping or sorting by zip code or in accordance with other criteria.
In a very popular type of insertion machine, an envelope and insert are respectively transported to an insertion station on two parallel tracks or conveyors, namely an insert track provided on a machine back table and an envelope track provided on a machine front table. Typically these tracks are indexed in a direction toward the insertion station in accordance with a machine cycle, e.g. with the track advancing essentially one track space toward the insertion station for every one revolution of a machine main timing shaft.
The insert track for the type of machine being described traditionally comprises a pair of endless chains which travel in front of a series of feeder stations. Each chain has a plurality of pusher pins provided thereon for causing inserts fed onto the chain pair to be driven in the direction toward the insertion station in accordance with machine timing.
At the insertion station, a three-fingered unit is used to shove a group of stacked, related inserts into an awaiting envelope. The three-fingered unit is connected to the distal end of a large, angularly swinging arm. The proximal end of the swinging arm is ultimately connected to the insertion machine mainframe so that a follower roller associated with the swinging arm follows a cam on the machine main drive shaft. The three-fingered unit drives the group of items into the awaiting envelope during a certain portion of the machine operating cycle.
An example of the type of insertion machine briefly described above is shown in U.S. Pat. No. 2,325,455 to A. H. Williams. Despite their mechanical intricacies, modern insertion machines of this type have amazing throughput and operate at very high speeds on the order of about 10,000 cycles per hour. It is a remarkable feat, for example, that by coordinated mechanical action, an insertion machine can register a group of inserts at an insertion station; open a flap . of an awaiting envelope; and, mechanically stuff a group of inserts into the open envelope with such rapidity. Yet, as the mailings prepared by such entities as financial institutions, utilities, governmental bodies and direct mail concerns continue to proliferate, it is evident that machines of comparable function but with even faster operational speeds would be welcome. Hence, an object of this invention is the provision of an insertion machine capable of high operating speeds, and in particular the provision of an insertion station and method of operating the same wherein groups of inserts are stuffed into envelopes in an expeditious and efficient manner.
Although rather infrequent, heretofore some problems have been experienced at conventional insertion stations of the type described above. On some occasions the eccentric connection of the angularly swinging arm has caused the multi-fingered shoving unit to bounce with respect to the insertion machine back table, with the result that the multifingered shoving unit may not be situated properly behind and beneath the stack of inserts for getting under those inserts and for driving those inserts into the awaiting, flap-opened envelope. On rare occasion such a bounce has resulted in the multi-fingered shoving unit actually moving above, rather than beneath, the stack of inserts. Hence, an advantage of the present invention is the provision of method and apparatus relative to an insertion machine having an insertion station whereat the means for shoving inserts into an awaiting envelope is consistently properly positioned for effectively shoving those inserts.
Prior art insertion stations which employed a shoving unit consisting of three fingers encountered problems when different sized inserts were included in a group, especially when rather small inserts were included in a group being stuffed into a relatively large envelope. In this regard, a small insert might be struck during the stuffing operation by just one fingers in which case the small insert might go askew into the envelope. Therefore, another advantage of the present invention is the provision of method and apparatus relative to an insertion machine having an insertion station wherein inserts of varied sizes are properly guided into awaiting envelopes.
When a group of inserts is being stuffed into an awaiting, opened envelope at very high speeds, there is a tendency for the inserts to bounce back and out of the envelope. In this regard, the unopened edge of the envelope is aligned with or at least proximate to an envelope stop plate during the insertion operation. When inserts are rapidly inserted into an awaiting envelope, the momentum of the inserts can carry the inserts against the envelope stop plate, from whence the inserts can bounce off sufficiently to possibly partially protrude from the envelope rather than being completely enveloped therein. Therefore, an advantage of the present invention is the provision of method an apparatus relative to an insertion machine having an insertion station whereat inserts are accurately placed into an awaiting, flap-opened envelope.
Since insertion machines operate at such phenomenally fast speeds, there is the possibility that a paper jam may occur every once in awhile at the insertion station. Heretofore, if a jam did occur at the insertion station, continued movement of the multifingered shoving unit could damage the jammed inserts. If one or more inserts in a group were damaged to the extent that they were unmailable, additional insert(s) would have to be prepared for that group, some of which may be inique to that group, such as a customer statement or the like, for example. Regeneration of unique document or insert of this type is very troublesome at this stage of operation. Therefore, another advantage of the present invention is the provision of method and apparatus relative to an insertion machine having an insertion station having means to protect inserts should a jam occur.
When jams have occurred at conventional stuffing stations, insertion machine operators generally attempt to manually clear the jam. In order to clear an insertion station jam, an operator can move away from the insertion station a device that is used to open the awaiting envelope. Typically this envelope opening device comprises a plurality of sucker cups, usually four, connected by elongated stems to a horzontally elongated carriage. The envelope-opening carriage is rotatable about a horzontal axis which essentially parallels the major dimension of the envelope. Accordingly, when a jam occurs at the insertion station, the envelope opening device can be rotated away from the insertion station, so that the jam can be cleared.
Unfortunately, there is a propensity among machine operators to lift the envelope opening device out of the way of the insertion station by grabbing the elongated sucker cup stems. Manipulation of the sucker cup stems in this manner tends to deform the stems, with the result that the sucker cups are not thereafter precisely positioned with respect to an envelope ushered therebeneath. Consequently, vacuum may not be properly applied through all envelope-opening sucker cups. Thus, another advantage of the present invention is the provision of method and apparatus relative to an insertion machine having an envelope-opening device which is easily movable for clearing jams at an insertion station.